Vector-Borne Illnesses
While some illnesses are transmitted by exposures to pathogens in the air or on surfaces, others are transmitted when an infected insect, like a mosquito or a tick, bites someone and exposes them to the pathogen that makes them sick. These are called vector-borne illnesses and often occur more frequently in the warmer summer months, but in recent years have been increasing year-round, likely due to changes in the climate. The goal of this tracker is to provide insight into recent weekly and geographic trends in several vector-borne illnesses.
Vector-Borne Illnesses by State
Trends Over Time
Select a condition or multiple conditions below to display the metrics for that condition.
Vector-Borne Illness Patients
September 2026
Monthly rates of vector-borne illness diagnoses per 100,000 patients who had office visits, emergency department visits, or hospital admissions.
Vector-Borne Illness Office Visit Patients
September 2026
Monthly rates of vector-borne illness diagnoses per 100,000 patients who had office visits.
Vector-Borne Illness ED Patients
September 2026
Monthly rates of vector-borne illness diagnoses per 100,000 patients who had emergency department visits.
Vector-Borne Illness Admitted Patients
September 2026
Monthly rates of vector-borne illness diagnoses per 100,000 patients who had hospital admissions.
Metric Definitions
- Malaria Diagnosis
- A diagnosis with an ICD-10-CM code of B50*, B51*, B52*, B53*, or B54*.
- Dengue Diagnosis
- A diagnosis with an ICD-10-CM code of A90 or A91.
- Lyme Disease Diagnosis
- A diagnosis with an ICD-10-CM code of A69.2*.
- West Nile Diagnosis
- A diagnosis with an ICD-10-CM code of A92.3*
- Rocky Mountain Spotted Fever (RMSF) Diagnosis
- A diagnosis with an ICD-10-CM code of A77.0.
- Babesiosis Diagnosis
- A diagnosis with an ICD-10-CM code of B60.0*.
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